Answer: Socratic
Explanation: i’m not sure but you can use Socratic it’s a good app that helps
Answer:
a) 16.32 m/s
b) 640 N
Explanation:
A) mass of rocket m_r = 1000 g = 1 kg
initial speed of rocket u_r = 15 m/sec
initial speed of ball is u_b = 18 m/sec
final speed of ball is v_b = 40 m/sec
Let m_b be the mass of the ball= 60 g and v_r be the final velocity of the rocket
from law of conservation of momentum
momentum of the system remains zero
m_r×(u_r-v_r)+m_b(16-42) = 0
1×(15-v_r) = -0.060(18-40)
15-v_r = -1.32
v_r = 15+1.32 = 16.32 m/sec.
B) Average force that the rocket exert's on the ball is F_avg can be calculated as
contact time t=7.00 ms
F_avg = m(v-u)/t = 0.06×(40+18)/0.007 = 640 N
Answer:
F1= 196 N
F2= 392 N
Explanation:
Given:
length of the plank = 2 m
mass of the plank = 20 kg
Weight of the plank = 20 x 9.8 =196 N
Torque due to the weight of the plank with respect to the pivoted end (i.e the end held by the hand) Counter clockwise torque = 196 x cog of wood
= 196 x 1 = 196 Nm
Clockwise torque = F2 x 0.5
for the balanced case
F2 x 0.5 = 196
F2 = 196/ 0.5
F2= 392 N
now,
the net force
Net downward force =Net upward force
F1 + weight of plank = F2
F1 + 196 = 392N
F1 = 392 – 196
F1= 196 N